Vehicle with adjustable occupancy space

ABSTRACT

A vehicle for providing adjustable occupant space has a fixed occupiable section defining a first interior space. The fixed occupiable section includes a number of ground engaging wheels and has a floor affixed to a number of walls. Also included is an expandable occupiable section moveably coupled to the fixed section which also has a floor fixed to at least one wall. The expandable section defines a second interior space intersecting the first interior space which is moveable relative to the first interior space to vary an amount of total living space defined by the fixed and expandable sections. A carriage for supporting the expandable section and selectively positioning it relative to the fixed section is included to adjust volume of the living space defined by both sections. This carriage includes at least one arm pivotably anchored to the first section which engages the expandable section in a load bearing relationship. An actuator with a stationary member fixed to the expandable section and a positioning member coupled to the load bearing arm is included. This positioning member is configured to selectively move relative to the stationary member in response to activation of the actuator to rotate the arms and correspondingly adjust the living space. By way of example, a coupling member provided on the load bearing arm is threaded onto a threaded shaft coupled to a motor, the coupling member and arm rotating with rotation of the threaded shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 08/585,163, filed Jan. 11, 1996, now U.S. Pat. No. 5,829,822and is a continuation-in-part of U.S. patent application Ser. No.08/584,060, filed Jan. 11, 1996 now U.S. Pat. No. 5,800,002.

BACKGROUND OF THE INVENTION

The present invention relates to a system for variably sizing a livingspace, and more particularly, but not exclusively, relates to areconfigurable living space system for a vehicle.

Recreational vehicles enjoy widespread popularity because they enabletheir owners to travel away from home for extended periods whileenjoying many of the comforts of home. One persistent limitation of suchvehicles is that their interior spaces are somewhat small and crampedcompared to a normal living space. While many factors contribute to thisdesign limitation, a major contributor is the relatively narrow width ofthe normal street or highway. The need to travel within the confines ofa normal highway traffic line sets an upper limit on the feasible widthof a recreational vehicle. Because this upper width limit is muchsmaller than the width of even a small room in a normal house, theinterior of a typical recreational vehicle seems cramped by familiarcomparison.

One ingenious solution to this problem is the incorporation of anexpandable room into a recreational vehicle such as a motor home or atrailer. This feature has found application in other types of trailersand vehicles having occupiable space.

U.S. Pat. No. 4,960,299 to Steadman shows a trailer with an expandableliving space provided, in part, by folding walls which pivot to aposition against the side of the trailer when not in an expandedconfiguration. U.S. Pat. No. 2,898,143 to Ferrera shows a trailer withmovable telescoping walls and a foldable floor which combine to providean expandable living space. U.S. Pat. No. 2,906,556 to Cantele et al.also shows an expandable trailer with a folding floor. This existingsystem uses pivoting walls to expand the sides and a telescoping wall inthe rear. Unfortunately, the folding walls and floors of these systemscomplicate the expansion process. Necessarily, these designs do notpermit one to continuously occupy the expandable section of the vehiclein both the expanded and unexpanded positions.

Consequently, slide out rooms have been developed which are continuouslyoccupiable in both the expanded and unexpanded positions. Quite often,these rooms are configured to emerge along an outer side wall of thevehicle when expanded. U.S. Pat. No. 5,295,430 to Dewald, Jr., et al.discusses slide out rooms and discloses a number of telescoping tubularsupports connected to the underside of the vehicle to laterally move theslide out room between the expanded and unexpanded positions. Thesesupports also must be configured to bear the load of the room in theexpanded position. Ideally, such load bearing function is performedwithout the need for ground engaging supports other than those requiredfor the vehicle in the unexpanded position.

One drawback with telescoping tubular support systems is theunacceptable frequency of binding between the slide out room and thefixed portion of the vehicle during movement. One system addresses thisproblem by adding a number of pulleys and cables to control motion ofone telescoping support relative to another. Unfortunately, such systemsgenerally increase complexity and expense.

Another drawback of telescoping tube support systems is that mounting ofthe supports occasionally requires significant gaps or voids in thevehicle chassis or frame--compromising structural integrity. For systemsusing a vehicle powered actuator to accomplish expansion, the threat ofbinding often limits the speed with which the telescoping members may bemoved. Thus, there is a need for a system to move and support expandableportions of a vehicle that resists binding without increasingcomplexity. This system should be lighter, faster, and more powerefficient than existing systems.

SUMMARY OF THE INVENTION

The present invention relates to systems for varying size of a livingspace. While the actual nature of the invention covered herein can onlybe determined with reference to the claims appended hereto, certainfeatures which are characteristic of the preferred embodiment of thenovel systems disclosed herein can be described briefly.

One aspect of the present invention is a system for varying space in avehicle which includes a fixed portion with occupiable space and anumber of ground engaging wheels, and an expandable portion coupled tothe fixed portion. The expandable portion has a rigid floor and ismovable relative to the fixed portion to adjust volume of a living spacedefined by the fixed and expandable portions. The floor is configuredfor planar movement along a generally horizontal plane when theexpandable portion is moved.

This system also includes a first load bearing arm engaging the floor tosupport the expandable portion. The first load bearing arm is pivotallyanchored to the fixed portion to rotate about a generally vertical firstaxis to correspondingly move the expandable portion. An operatorcontrolled actuator is coupled to the first load bearing arm toselectively rotate the first load bearing arm and thereby controlposition of the expandable portion relative to the fixed portion toprovide adjustment of the living space.

Another aspect of the present invention is a vehicle which providesadjustable occupant space that has a first occupiable section with anumber of ground engaging wheels and a second occupiable section coupledto the first section. The vehicle also includes a carriage forsupporting the second section and selectively positioning it relative tothe first section to adjust volume of the living space defined by bothsections. This carriage includes at least one load bearing arm pivotablyanchored to the first section which is configured to rotate about anaxis to position the second section. An actuator with a stationarymember is fixed to the second section and has a positioning membercoupled to one or more load bearing arms of the carriage. Thepositioning member is configured to selectively move relative to thestationary member in response to activation of the actuator andcorrespondingly rotate the arms to adjust the living space of thevehicle. The one or more load bearing arms of the carriage may include apivotably mounted coupling member which defines a threaded boretherethrough. For this configuration, the positioning member includes athreaded shaft threaded through the bore of the coupling member, and theactuator is configured to rotate the shaft to position the couplingmember therealong and correspondingly rotate the arm to adjust theliving space. In other embodiments, the arrangement may vary.

One object of the present invention is to provide a rotatable armsupport system for moving the expandable section of a vehicle.

Another object is to reduce binding, increase adjustment speed, andimprove efficiency of a system for adjusting the volume of a livingspace that has fixed and expandable portions.

Still another object of the present invention is to provide a loadbearing rotatable arm support system with an actuator fixed to theexpandable portion and coupled to at least one support arm.

Yet another object is to position rotatable load bearing arms for theexpandable section of a vehicle by turning a threaded shaft coupled tothe arms.

Further objects, advantages, and features of the present invention willbe made apparent from the drawings and description contained herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is perspective view of a vehicle of one embodiment of the presentinvention;

FIG. 2 is a diagrammatic partial cross-sectional view of the vehicleshown in FIG. 1;

FIG. 3 is a partial side perspective view of a carriage for theembodiment of FIG. 1;

FIG. 4 is a top plan view of the carriage shown in FIG. 3;

FIG. 5 is a partial cross-sectional elevational view taken along line5--5 of FIG. 4;

FIG. 6 is a partial diagrammatic depiction of an actuation system forthe present invention;

FIG. 7 is a cutaway top plan view of a slidable floor system for theembodiment of FIG. 1;

FIG. 8 is a partial side sectional view of the floor system shown inFIG. 7;

FIG. 9 is a top view of a coupling latch of another embodiment of thepresent invention;

FIG. 10 is a top view of the embodiment shown in FIG. 9;

FIG. 11 is a cross-sectional view taken along line 11--11 of FIG. 10;

FIG. 12 is an elevational side view of the embodiment shown in FIG. 9;

FIG. 13 is a cutaway side view of a coupling system of yet anotherembodiment of the present invention.

FIG. 14 is a diagrammatic top view of one state of operation of theembodiment shown in FIG. 13;

FIG. 15 is a diagrammatic top view of the embodiment of FIG. 13 in adifferent state of operation;

FIG. 16 is a diagrammatic top view of the embodiment of FIG. 13 in yetanother state of operation;

FIGS. 17 and 18 depict a cross-sectional, partial top view of anexpandable room system of still another embodiment in expanded andretracted positions, respectively; and

FIG. 19 is a partial cross-sectional elevational view of the embodimentshown in FIGS. 17 and 18.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, any alterations and further modificationsin the illustrated device, and any further applications of theprinciples of the invention as illustrated therein being contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

FIGS. 1 and 2 depict vehicle 10 of one preferred embodiment of thepresent invention. Vehicle 10 has a number of ground engaging wheels12a, 12b, 12c; a fixed section 20; and an expandable section 40. Vehicle10 also includes a compartment 14 for housing a means to move andsupport expandable section 40 relative to fixed section 20. Fixedsection 20 includes internal walls 22 and external wall 24. Fixedsection 20 further includes roof 28 and floor 30 generally opposing oneanother. Collectively, the structures of fixed section 20 define a fixedsection living space 20a.

Expandable section 40 includes opposing walls 42, 44 and outer wall 46.Opposing walls 42, 44 and outer wall 46 are joined to roof 48. Roof 48opposes floor 50. Floor 50 is correspondingly joined to opposing walls42, 44 and outer wall 46. Opposing wall 42 includes a window 45. Outerwall 46 includes a window 45 and a skirt portion 49. Skirt portion 49has a storage compartment or bin 49a for the storage of miscellaneousitems. Bin 49a has an access door 49b for access from the exterior oroutside of vehicle 10. Expandable section 40 defines an occupiableliving space 40a.

Vehicle 10 defines an interior living space 10a comprising fixed sectionliving space 20a and expandable section living space 40a. Vehicle 10 haswindows 25 and door 27 and includes furnishing 16a, 16b, 16c, 16e, and16f configured in the conventional manner for a motor home. Vehicle 10is also motorized in the conventional manner and includes drivingcompartment 17 configured in a way common to motor homes and the like.

Expandable section 40 is configured to move relative to fixed section 20along an axis T. This movement facilitates selective adjustment ofexpandable section 40 between the expanded position shown in FIG. 1 andthe unexpanded position shown in FIG. 2. In the unexpanded position,outer wall 46 is generally flush with external wall 24. Unlike manyexisting systems, the expandable section 40 may be occupied in theunexpanded as well as expanded positions. Similarly, the fixed section20 is occupiable whether the expandable section 40 is expanded orunexpanded.

FIGS. 3-5 illustrate a carriage 100 for moving and supporting expandablesection 40 relative to fixed section 20. Expandable section 40 is notshown for clarity in FIG. 3. Similarly, expandable section 40 is onlyshown partially in FIGS. 4 and 5. Carriage 100 includes anchor brackets110, 120 rigidly attached to fixed section 20 of vehicle 10. In FIGS. 3and 4, brackets 110, 120 are attached to a C-shaped vehicle frame member18. In FIG. 5, bracket 110 is shown attached to an I-shaped vehicleframe member 18a. In either case, bolted attachment plates areillustrated as the means of rigid attachment. Alternatively, welding orsome other conventional attachment means may be used.

Notably, neither bracket 110, 120 passes through the vehicle frame andthereby avoids significantly compromising structural integrity of thevehicle chassis. Each bracket 110, 120 has a generally horizontal topmember 111, 121 and a bottom member 112, 122 joined by generallyvertical members 113, 123 and gusset members 114, 124. Each bracket 110,120 also includes angle brace 116, 126. Brackets 110, 120 are eachcoupled to frame 18 along vertical member 113, 123 and with angle brace116, 126. As more clearly seen in FIG. 5, bottom members 112, 122 have aportion which extends under frame 18 or 18a to provide better loadbearing support.

Load bearing arms 130, 140 are pivotably anchored to brackets 110, 120,and are correspondingly pivotally connected or attached to fixed portion20 of vehicle 10. Each arm 130, 140 has an anchor portion 130a, 140aopposing a bearing portion 130b, 140b. Anchor portions 130a, 140a andbearing portions 130b, 140b are integrally and rigidly connected to eachother. Arms 130, 140 include generally horizontal elongated top members131, 141 and support members 132, 142 connected by gusset 134, 144.Generally, vertical tubes 133, 143 are positioned between top members131, 141 and support members 132, 142 and slightly protrude through abore in each. For each arm 130, 140, a corresponding bearing pin 135,145 passes through top member 131, 141; tube 133, 143; and supportmember 132, 142. Each bearing pin 135, 145 is fastened to a bracket 110,120, respectively.

Bearing pins 135, 145 each lie along a generally vertical rotationalaxis R1, R2. Arms 130, 140; tubes 133, 143; and bearing pins 135, 145are configured so that each arm 130, 140 rotates about axis R1, R2,respectively.

Arms 130, 140 are also each configured to include an oblique portion136, 146. Oblique portion 136, 146 is positioned at an oblique anglewith respect to a longitudinal axis along top members 131, 141. Obliqueangle A is illustrated in FIG. 4 for arm 140. Preferably this angle isin a range of about 100 to 130 degrees. More preferably, the angle is ina range of about 110 to 120 degrees. Most preferably, the angle is about115 degrees.

Rod 150 is pivotally connected to each oblique portion 136, 146. Eachoblique portion 136, 146 defines a cavity 137, 147 configured to form aclevis connection in conjunction with pins 138, 148 to pivotally connectto opposing ends 150a, 150b of rod 150. When so connected, rod 150 spansa distance between arms 130, 140 and pivotably couples arms 130, 140together. Rod 150 further includes opposing mounting sections 154a, 154bcorresponding to each end 150a, 150b. Also, rod 150 has an elongatedturnbuckle segment 156 threadingly engaging each mounting section 154a,154b. Mounting segments 154a, 154b and turnbuckle segment 156 areconfigured so that rotation of turnbuckle segment 156 about itslongitudinal axis provides a turnbuckle function to adjust the effectivelength of rod 150. In turn, this adjustment controls the relativespacing of arms 130, 140 coupled to rod 150. Stopping nut 158threadingly engages mounting segment 158a of rod 150 at the interfacewith turnbuckle segment 156 to prevent unwanted rotation of turnbucklesegment 156 once adjustment has been accomplished. Stopping nut 158 maybe turned about mounting segment 154a relative to turnbuckle segment 156to allow readjustment as needed.

In one preferred embodiment, each bracket 110, 120 and arm 130, 140 ismanufactured from metal tubes using conventional joining methods. Inother embodiments, different shapes or materials may be used as wouldoccur to one skilled in the art.

Next, actuation system 160 for carriage 100 is discussed. Actuationsystem 160 includes an operator controlled hydraulic pump 162 coupled toa double acting hydraulic cylinder 170. Both pump 162 and cylinder 170are of a conventional type. Coupling between the pump 162 and hydrauliccylinder 170 is accomplished by fluid conduits 164, 166. Pump 162 mayalso service other actuation systems for vehicle 10. Hydraulic cylinder170 includes a body 171 and a mounting ear 172 pivotably mounted toangle brace 116 by fastener 173. Hydraulic cylinder also has a plunger174 with a mounting portion 176 pivotably mounted to support member 132by fastener 177.

Each arm 130, 140 includes a slide block 180, 190 on a spindle 182, 192threadingly engaging a threaded bore in each bearing portion 130b, 140b.The height of each slide block 180, 190 is adjusted relative to arm 130,140 by turning spindle 182, 192 to advance it up or down with respect tobearing portion 130b, 140b, and locking spindle 182, 192 in place withstopper nut 184, 194. As illustrated in FIG. 5, spindle 182 has an end186 that is preferably not threaded which engages a recess in each slideblock 180. It being understood that spindle 192 and slide block 190 aresimilarly configured (not shown). Each slide block rests on spindle 182,192 to pivot about an axis along the length of each spindle 182, 192.This rotational axis for spindle 182 is shown as axis R3 in FIG. 5.

FIGS. 4, 5, and 7 depict the relationship of floor 30 of fixed section20 with floor 50 of expandable section 40. Notably floor 30 isunderneath floor 50 and floor 50 is configured to slide along floor 30when expandable section 40 is adjusted between expanded and unexpandedpositions. Floor 50 is rigid and planar and generally moves along ahorizontal plane. Also, floor 50 includes a guide slot 54 along theouter wall 46 of expandable section 40. Slot 54 is situated betweenouter side 56 and inner side 58. Generally, slot 54 is oriented along ahorizontal axis perpendicular to the R1, R2, R3, and T axes. Each slideblock 180, 190 engages slot 54 and is configured to slide therealong.The height of floor 50 relative to floor 30 and carriage 100 may bevaried by adjusting the position of spindles 182, 192 in bearingportions 130b, 140b.

Having described the structure of carriage 100, the operation ofcarriage 100 and its application in vehicle 10 is next discussed. FIG. 3shows carriage 100 in a retracted position corresponding to anunexpanded position of expandable section 40. FIG. 4 shows carriage 100in an extended position corresponding the the expanded position ofexpandable section 40. FIG. 4 depicts arcuate paths P1 and P2 of arms130, 140 when rotated about R1, R2, respectively. Also, the retractedposition of arms 130, 140 are shown in FIG. 4 in phantom.

With carriage 100 starting in a retracted position, plunger 174 is at aminimal length being mostly nested within body 171 of hydraulic cylinder170. To rotate arms 130, 140 and correspondingly move expandable section40 relative to fixed section 20, pressurized hydraulic fluid is sent bycontrollable hydraulic pump 162 through conduit 164 to push a pistonattached to plunger 174 inside body 171 (not shown). Plunger 174 iscorrespondingly pushed out of hydraulic cylinder 170 and pushed againstarm 130 via mounting portion 176. Arm 130 correspondingly pivots inrelation to hydraulic cylinder 170 and also swings outward away fromvehicle 10 along path P1--rotating about axis R1.

As arm 130 rotates outward, oblique portion 136 correspondingly rotatesto push rod 150. Rod 150 correspondingly pushes oblique portion 146 ofarm 140 and causes arm 140 to rotate outward along with arm 130. In thismanner, the pivotable linkage of rod 150 between arms 130 and 140provides for the tandem rotation of arms 130, 140 upon rotation ofeither arm by an actuator such as hydraulic cylinder 170. The tandemrotation of arms 130, 140 correspondingly moves slide blocks 180, 190along slot 54, and slide blocks 180, 190 push outward against outer side56 to correspondingly move floor 50 laterally outward from fixed section20. Floor 50 generally slides on floor 30 along a horizontal plane.Because floor 50 is coupled to expandable section 40, expandable section40 moves outward with rotation of arms 130, 140. Extension of carriage100 and the corresponding expanded position of expandable section 40 isillustrated in FIGS. 1, 4, and 5.

Retraction of carriage 100 is accomplished by configuring hydraulic pump162 to send pressurized fluid through conduit 166 to correspondinglyretract plunger 174 into body 171 of double acting hydraulic cylinder170. Correspondingly, plunger 174 pulls against arm 130 which causesrotation of arm 130, and also arm 140 through the pivotal connection ofrod 150 to oblique portions 136, 146.

During retraction, slide blocks 180, 190 slide in slot 54 in a directionopposite the direction traveled during extension. Correspondingly,during retraction, slide blocks 180, 190 pull against inner side 58 topull floor 50 of expandable section 40 inward Likewise expandablesection 40, joined to floor 50, is correspondingly pulled inward towardvehicle 10. FIGS. 2 and 3 show carriage 100 in the retracted position.

Not only do arms 130 and 140 provide for controlled movement ofexpandable section 140, but also bear the load of expandable section 40in the expanded position without the need for additional ground engagingsupports. Generally, the load bearing arm structure of carriage 100 islighter weight and takes up less space relative to conventionaltelescoping tube supports. In part, this efficiency is related to thecantilever configuration of arms 130 and 140. As shown for arm 130 inFIG. 5, arm 130 has a distance Y which corresponds to the hinge lengthof the pivoting anchor attachment of anchor portion 130a to bracket 110along axis R1. Arm 130 also has a support length X generallyperpendicular to axis Ri as shown in FIG. 5. In part, the load bearingcapability of arm 130 is determined as a function of a supportratio=support length÷hinge length. For FIG. 5, the support ratio=X÷Y. Itis preferred that the support ratio be in a range of about 1-3. It ismore preferred that the support ratio be in a range of 2.4 to 2.8. It ismost preferred that the support ratio be about 2.6.

In other embodiments, load bearing arms may be configured outside thisrange, and indeed may be configured so that anchor portions and bearingportions are not rigidly attached to one another, but instead articulatewith respect to each other. In still other embodiments, support arms areconfigured as simple beams having ground engaging supports in theextended position. Although a two swing arm carriage 100 is preferred,fewer or more arms are also contemplated in alternative embodiments.Also, arms 130, 140 may be configured to engage a slot in outer wall 46instead of floor 50. Alternatively, rollers or wheels may be used inplace of slide blocks 180, 190.

Preferably, expandable section 40 is illustrated as a relatively rigidroom with side walls 42, 44, outer wall 46, roof 48, and floor 50 allrigidly coupled together in relation to one another to form atelescoping section slidingly coupled to fixed section 20. Thisconfiguration of expandable section 40 permits continuous occupancywhether in the expanded or unexpanded position. In alternativeembodiments, fewer or less walls may be used and the floor or roof maynot be coupled to the walls. Instead, the floor, roof, and walls may beseparately extendable or movable in relation to the rest of theexpandable section. In addition, the walls, floor, or roof may befoldable or pivotable in relation to the rest of the expandable sectionin alternative embodiments. Also, expandable section 40 may beconfigured to emerge from the rear of a vehicle as well as from theside.

FIG. 6 illustrates an alternative actuation system 200 for use withcarriage 100 of the present invention. Carriage control system 200includes a controllable hydraulic pump system 262 including acontrollable valve portion 263 and a control signal portion 269. Pumpsystem 262 is selectively powered by vehicle electrical battery 210 bycoupling to the depicted +/- terminals with a safety fuse 212 interposedon the positive voltage side. Battery 210 and pump system 262 are of aconventional design. Controllable valve portion 263 is coupled tohydraulic actuator 270 by conduits 264 and 266.

Control circuit 250 is coupled to the positive side of battery 210 viafuse 214. Control circuit 250 comprises a number of switches 220, 230,240 coupled in series between fuse 214 and control signal portion 269.Control switch 240 is a multiposition, multipole switch for controllingactivation of pump system 262 which correspondingly controls actuationof hydraulic actuator 270. Preferably, control switch 240 is of aspring-loaded rocker design which has two active positions and a "centeroff" position. In order for control switch 240 to send the appropriatecontrol signals to pump system 262, switches 220 and 230 must be closedso that current can flow through circuit 250 to control switch 240.

Switches 220 and 230 are both safety switches to prevent inadvertant orunauthorized use of system 200. Key lock switch 220 is provided toprevent unauthorized actuation, and is preferably a single pole, singlethrow switch which requires a key to operate. Emergency brake switch 230is coupled to an emergency brake (not shown) for vehicle 10 eithermechanically or electrically and is preferably configured as a singlepole, single throw switch which is only closed if the emergency brake isset. As a result both safety switches 220 and 230 must be electricallyclosed by using the appropriate key and setting the emergency brake,respectively, before pump system 262 may be activated.

In a schematic cross-sectional view, hydraulic actuator 270 has a body271 defining chambers 271a and 271b separated by piston 273 which isconnected to plunger 274. Body 271 has a mounting ear 272 and plunger274 has threads 278 up to the mounting end 279 outside of body 271.Threads 278 on mounting end 279 may be engaged to couple plunger 274 toa carriage swing arm or other mechanism requiring actuation, usingconventional methods. Nut 277 is also configured to engage threads 278along the length of plunger 274. Body 271 defines openings 270a, 270bfor corresponding connection to conduits 264, 266 from pump system 262.Hydraulic actuator 270 also includes stops 275 to limit travel of piston273 so that outlets 270a, 270b are not blocked.

The function of actuation system 200 is next discuss(ed. Safety key lockswitch 220 and emergency brake switch 230 of control circuit 250 must beclosed to activate actuation system 200. Once switches 220 and 230 areclosed, control switch 240 is able to selectively actuate actuator 270via pump system 262. In one position control switch 240 sends a signalto pump system 262 which causes system 262 to supply pressurizedhydraulic fluid into chamber 271a through conduit 264 and outlet 270a.Piston 273 is correspondingly pushed away from outlet 270a and plunger274 moves out of body 271. For this position, pump 262 is alsoconfigured to allow fluid present in chamber 271b to flow toward pump262 through outlet 270b and conduit 266.

Control switch 240 also has a second position to reverse the directionof plunger 274 relative to the first position. The second position sendsa signal to pump system 262 to cause pressurized hydraulic fluid to flowthrough conduit 266, outlet 270b, and into chamber 271b. The fluid inchamber 271b pushes against piston 273 to cause plunger 274 to retractinto body 271.

For one preferred embodiment, the amount of retraction or extension ofplunger 274 with respect to body 271 is controlled by the amount of timecontrol switch 240 is engaged in either the first or second position andthe stroke of plunger 274 within body 271. Stoppers 275 limit the strokeor travel length of plunger 274 to prevent blockage of outlets 270a,270b. Control switch 240 is also configured with an off position whichmaintains the plunger 274 in a selected position. Preferably, pumpsystem 262 is able to detect if a stroke limit has been reached and takeappropriate action to prevent damage to system 200.

Besides stoppers 275, additional stroke length adjustment is provided bynut 277 when threaded on plunger 274. Nut 277 may be selectivelypositioned along plunger 274 by turning nut 277 about the longitudinalaxis of plunger 274. Adjustment of nut 277 therealong provides furtherlimiting of the degree of retraction of plunger 274 into body 271. Usinga hydraulic actuator 270 configured in this manner as a substitute forhydraulic cylinder 170 in carriage 100, the nut 177 may be utilized tofine tune for tolerances of the carriage structure. As a result,stresses which are caused by "overretraction" of a plunger can beavoided. Avoidance of such stresses on carriage members further enhancesthe ability to avoid binding.

In an alternative embodiment, an electromechanical actuator isenvisioned instead of a linear hydraulic actuator like 270. In anotheralternative embodiment two single acting hydraulic cylinders are used inplace of a double acting hydraulic actuator. In this configuration, eachsingle acting cylinder operates in a direction reverse to the other. Ina variation of this configuration, each cylinder is coupled to adifferent load bearing arm in a swing arm configuration similar tocarriage 100. In still another embodiment, an operator powered system isenvisioned using a foot pump or hand crank.

Pump system 262 may additionally be used to actuate other hydraulicsystems for the vehicle. Also, instead of control circuit 250, system200 may be modified to interface with a microprocessor based system in aconventional manner.

Referring to FIGS. 5, 7, and 8, another aspect of the present inventionis shown. Floor 50 of expandable section 40 includes guide rails 59a-59dwhich are generally parallel to the direction of travel of expandedsection 40 along axis T. These rails are preferably made from aself-lubricating polymeric resin. In one preferred embodiment, the railmaterial includes nylon.

Each guide rail slides in a corresponding guide slot 39a-39d. Slots39a-39d are defined by a support surface 35 of a raised floor portion 32of floor 30. An outer edge 34 of raised floor portion 32 is shown inphantom in FIG. 7. Edge 34 is generally flush with external wall 24.Each guide slot 39a-39d also is generally parallel with axis T. Inalternative embodiments, at least a portion of each guide rail 39a-39dmay include a self-lubricating polymeric resin--such as nylon--either asan alternative to the composition of rails 59a-59d from aself-lubricating polymeric resin or in addition to rails 59a-59d beingmade from a self-lubricating polymeric resin.

Rails 59a-59d slide along guide slots 39a-39d as expandable section 40is moved relative to fixed section 20. The rails 59a-59d provide asimple alternative to rollers or wheels common to existing systems, butat the same time, the self-lubricating properties of the rail/slotconfiguration sacrifices little in terms of performance. Generally, thisrail/slot arrangement enhances nonbinding travel of expandable section40.

In other embodiments, more or less rails in corresponding slots areenvisioned. Also, the fixed portion may have one or more rails incorresponding slots defined by the movable floor. The rail/slotarrangement of the present invention may also be used independent of thetype of expansion system or expandable portion configuration.Furthermore, other embodiments of the present invention may not employthe guide rail/slot configuration feature.

Next referring to FIGS. 9-12, a coupling latch 300 of the presentinvention is shown. The coupling latch 300 has a member 310 withopposite sides 312, 314 and opposite ends 316, 318. Member 310 has a topsurface 326 opposite a bottom surface 328. Side 314 defines a notch 330with interface 332. Member 310 also has guide shoulders 321, 322, 323,and 324.

Member 350 includes guide rails 352, 354 opposing each other. Guiderails 352, 354 define a channel 356 therebetween. Channel 356 has anentry end 357 and terminal end 359. Terminal end 359 is bounded byheader 360 configured with shoulder sides 361, 362. Member 350 has a topsurface 366 opposite a bottom surface 368. Rail 354 defines a notch 370intersecting channel 356. Notch 370 has a floor 372.

Referring to FIG. 9, operation of coupling latch 300 is next discussed.Member 310 moves relative to member 350. Member 310 is configured toslide between guide rails 352, 354 and into channel 356 along arrow S1.Preferably, member 310 is configured to fit snugly between rails 352,354. Movement along arrow S1 is stopped by header 360 when end 316reaches terminal end 359 as shown in FIG. 10. Notably, shoulders 321,322 help to guide end 316 of member 310 into entry end 357 of channel356.

When end 316 meets header 360, notch 330 aligns with notch 370 to formcavity 380 as shown in FIGS. 10 and 12. FIGS. 10-12 also show a couplingpin 390 inserted into cavity 380. Pin 390 snugly fits into cavity 380 toprevent substantial movement of member 310 relative to member 350 alongany plane parallel to the view plane of FIG. 10. Member 310 cannot bemoved along directional arrow S2 without breaking or deforming at leastone of members 310, 350, and pin 390.

Referring to FIG. 11, coupling pin 390 is shown with opposing sides 391,392. Notably, when engaged in cavity 380, side 392 contacts side 354a ofguide rail 354 and side 391 contacts side 314 of member 310.

As illustrated, members 310, 350 are configured as substantially planarplates; however, in other embodiments, one or more of members 310, 350,and pin 390 may be shaped differently, as would occur to one skilled inthe art. For example, member 350 need not have a header 360 tofacilitate alignment of notches 330 and 370. Also, some embodiments donot have shoulders 321, 322, 323, and 324, or these shoulders are shapeddifferently. In addition, interface 332, floor 372, or both may beabsent. In a embodiment having neither interface 332 nor floor 372,chamber 370 becomes a bore so that coupling pin 390 may completely passthrough members 310 and 350 during latching. However, even withoutinterface 332, and floor 372, pin 390 need not pass completely througheither member 310 or member 350 to substantially prevent movement ofmember 310 relative to member 350. As a result, coupling latch 300provides a way to interlock two bodies together that are movable inrelation to each other without needing to align holes for the passage ofa coupling pin therethrough.

Members 310, 350 can each be mounted on walls or other surfaces movablein relation to each other to provide for selective coupling with pin 390Similarly, either member may be defined or formed from a continuoussurface.

FIGS. 13-16 illustrate a coupling system for an enclosure using acoupling latch of the present invention. Housing system 400 includeswalls 401 and 402 movable relative to each other along axis M. Generallywalls 401 and 402 are parallel to each other, and move along a planeparallel to axis M. In one embodiment, walls 401 and 402 are part of avehicular enclosure having an expandable portion and a fixed portion.

FIG. 13 shows a cutaway side view of coupling members 450 and 470extending from wall 402. Coupling finger 410 projects from wall 401 andis selectively movable between coupling members 450, 470 along axis M aswall 401 moves relative wall 402. Coupling finger 410 has opposite ends416, 418 and opposite sides 412, 414. Side 414 defines a notch 430.Coupling member 450 has opposing guide rails 452, 454 defining channel456 therebetween. Channel 456 terminates at header 458. Guide rail 454defines notch 460 intersecting channel 456. Coupling member 470 hasopposing guide rails 472, 474 defining channel 476 therebetween. Channel476 terminates at header 478. Guide rail 474 defines notch 480intersecting channel 476. The illustration of FIG. 13 contemplatesfinger 410 and members 450, 470 as separate bodies that are attached towalls 401,402 using conventional methods; as integral unitary portionsor formations of walls 401, 402 defined by the respective wall surfaces;or a combination of these depictions.

FIGS. 14-16 are partial top sectional views of the embodiment shown inFIG. 13 with walls 401 and 402 in different relative positions. In FIG.14, coupling finger 410 is illustrated as a projection from wall 401 andis shown engaged in channel 476 so that notches 430 and 480 align toform chamber 482. Chamber 482 aligns with aperture 406 defined by wall401. In addition, coupling pin 490 is shown coupled to controllableactuator 492. Actuator 492 is attached to wall 401 opposite finger 410so that coupling pin 490 may pass through aperture 406. Activation ofactuator 492 causes coupling pin 490 to pass through aperture 406 andengage chamber 482. When engaged in chamber 482, pin 490 preventsseparation of finger 410 from coupling member 470 in a manner describedfor coupling latch 300. Wall 401 extends past corner wall 402a which maycorrespond to the extended position of expandable section 40 such asshown in FIG. 1.

FIG. 15 shows an intermediate position of finger 410 between couplingmembers 450 and 470. This position of finger 410 corresponds to movementof walls 401 and 402 relative to one another between coupling positions.Coupling pin 490 is disengaged from coupling member 470 and is retractedinto housing 494 of actuator 492.

FIG. 16 shows another coupling position of walls 401 and 402corresponding to engagement of finger 410 in channel 456 of couplingmember 450. When finger end 416 meets header 458, notch 430 is alignedwith notch 460 to form chamber 484. Coupling pin 490 is engaged inchamber 484 to interlock coupling member 450 and finger 410 together,preventing substantial movement of walls 401, 402 relative to eachother. Corner walls 402a, 401a are generally aligned which maycorrespond to the unextended position of expandable section 40 shown inFIG. 2.

In another embodiment, wall 402 is configured to define a channel withappropriately spaced intersecting side notches as a substitute formembers 450, 470. For a substantially planar wall as shown in FIGS.13-16, the notched channel of this configuration would generally liebelow the plane of the wall surface.

Actuator 492 may be a solenoid or hydraulically controlled device of aconventional type. Preferably, actuator 492 holds pin 490 in engagementwith chamber 482 even when the power source for the actuator fails. Inother embodiments, actuator 492 is a spring-loaded faster operatedmanually or another type of actuator conventionally used to directlinear motion of a body. It is also preferred that actuator 492 becoupled to a control system which prevents inadvertent release ofcoupling pin 490 from chamber 482 when such release can adversely impactsafety. One example is the application of the system shown in FIGS.13-16 to provide for selective coupling of an expandable portion of avehicle in expanded and unexpanded states.

FIGS. 17-19 depict various aspects of expandable room system 500 for avehicle. FIGS. 17 and 18 provide a partial, cross-sectional top view ofsystem 500 in an expanded and retracted position, respectively. FIG. 19provides a partial, cross-sectional side view of system 500. System 500may be adapted for use with the vehicle described in FIGS. 1 and 2 andaccompanying text. System 500 includes a fixed section 510 of thevehicle which has an underlying chassis 512 and floor 514 Also depictedare walls 516, 517 fixed to floor 514. Preferably, fixed section 510 issimilar in configuration to fixed section 20 depicted in FIGS. 1 and 2,although other configurations as would occur to one skilled in the artare also contemplated.

Fixed section 510 defines cavity 518 to house carriage 530. Carriage 530is configured to position expandable section 520 to adjust volume at aliving space defined by sections 510 and 520. Expandable section 520includes floor 524 fixed to outer wall 525 and opposing side walls 526,527; however, floor 524 is depicted in a cutaway view in FIGS. 17 and 18to more clearly present certain other features. Expandable section 520is configured to move relative to section 510 to provide a range ofpositions which vary the position of the interior occupiable space ofsection 520 within the interior space defined by fixed section 510. Twopositions within this range are depicted in FIGS. 17 and 18,respectively.

Carriage 530 includes two swing arm mechanisms 540, 550. Each swing armmechanism 540, 550 includes a corresponding anchor bracket 542, 552,fixed to chassis 512 of fixed section 510 within cavity 518. Each swingarm assembly 540, 550 also includes a rotatable load bearing arm 544,554 configured to rotate about a corresponding axis 540b, 550b. Axes540b, 550b correspond to pivot points 540a, 550a. Preferably, anchorbrackets 542, 552 are configured similar to brackets 110, 120 depictedin FIGS. 3-5. It is also preferred that load bearing arms 544, 554 havea support ratio similar to arms 130, 140 of carriage 100 depicted inFIGS. 3-5. Moreover, it is preferred that brackets 542, 552 and arms544, 554 be manufactured from a metallic or composite material suitablefor movement and support of section 520.

Arms 544, 554 also include corresponding coupling members 546, 556configured to engage expandable section 520 for positioning relative tosection 510. As such, coupling members 546, 556 also serve as bearingmembers for engaging section 520. Coupling members 546, 556 arepivotably mounted on spindles 547, 557 to pivot about pivot points 547a,557a and corresponding pivot axes 547b, 557b. Spindles 547, 557 may beconfigured to provide for vertical adjustment as described in connectionwith spindles 182, 192 of the embodiment depicted in FIGS. 3-5. Eachcoupling member 546, 556 defines a threaded or tapped bore 548, 558through its body.

Carriage 530 also includes actuator 560. Actuator 560 includes electricmotor 562 with power/control cable 564 operatively coupled thereto.Motor 562 includes a stationary base 563 preferably fixed to expandablesection 520 on an underside surface of floor 524. Motor 562 includes arotatable shaft 566 coupled to threaded shaft 570. Threaded shaft 570 isthreaded through bores 548, 558 of coupling members 546, 556,respectively. Shaft 570 has first end portion 570a opposite second endportion 570b. End portion 570a is attached to coupling shaft 566 andmotor 562. Bearing journal 572 rotatably couples end portion 570b tosection 520. Between end portions 570a, 570b, coupling members 546, 556are threaded along shaft 570. Furthermore, shaft 570 and couplingmembers 546, 556 are located within guide track 574. Guide track 574 hasopposing rails 576a, 576b defining channel 577 therein for shaft 570 andcoupling members 546, 556. Notably, axes 540b, 547b, 550b, 557b aregenerally parallel to one another and approximately vertical; however,expandable section 520 moves along a generally horizontal planecoincident with travel axis T1. Motor 562 is preferably coupled to anoperator control which permits an operator to selectively rotatecoupling shaft 566 and shaft 570 in a clockwise or counterclockwisedirection, and further to selectively stop rotation of motor 562. It ispreferred that shaft 570 be machined from a steel alloy with an acmestyle thread. Preferably, coupling members 546, 556 are configured asslide-blocks with a self-lubricating material such as nylon or anultra-high-molecular-weight-polyethylene compound.

In operation, system 500 positions section 520 relative to section 510by rotating arms 544, 554 over the range indicated by arcs A1, A2 inFIG. 17. Actuator 560 provides for selective rotation of arms 544, 554in accordance with input from an external operator control (not shown).Specifically, motor 562 responds to this input by rotating couplingshaft 566 and threaded shaft 570. Because end portions 570a, 570b ofshaft 570 are both journaled to expandable section 520, this rotationdoes not provide a net displacement of shaft 570 with respect to section520. However, because coupling members 546, 556 are threaded along shaft570 these members tend to move along shaft 570 as it is rotated.Assuming bores 548, 558 are threaded in a common direction and thethreading of shaft 570 is consistent, the direction of motion ofcoupling members 546, 556 relative to arrow S depends on the directionof rotation of shaft 570, and the direction of the threading of shaft570 and bores 548, 558. When shaft 570 is rotated in one direction,coupling members 546, 556 move in tandem in the direction indicated byarrow S. By reversing this direction of rotation, coupling members 546,556 move in tandem in the opposite direction. As coupling members 546,556 move along shaft 570, generally constant spacing is maintainedtherebetween and the pivotal position about axes 547b, 557b of couplingmembers 546, 556 relative to arms 544, 554 changes, respectively. Inresponse, arms 544, 554 rotate about axis 540b, 550b, and move alongarcs A1, A2, correspondingly. Expandable section 520 moves with arms544, 554 through the bearing relationship of coupling members 546, 556with section 520. Consequently, the rotational motion of motor 562,coupling shaft 566, and threaded shaft 570 is converted into thetranslational motion of expandable section 520 along axis T1 by carriage530. When shaft 570 is rotated to move coupling members 546, 556 in thedirection indicated by arrow S, then the total volume of living space isexpanding with the corresponding movement of section 520. When rotationof shaft 570 is reversed, the coupling members move in the oppositedirection indicated by arrow S to retract section 520. A retractedposition is shown in FIG. 18 and a retracted position of arms 544, 554is indicated in FIG. 17 in phantom.

Guide 574 serves to protect shaft 570 from debris and rails 576a, 576bprovide additional bearing surfaces for coupling members 546, 556.Specifically, coupling members 546, 556 may push against rail 576bduring expansion and pull against rail 576a during retraction, while atthe same time sliding against the rails 576 as they move along rotatingshaft 570. Besides a rotational actuation mechanism 560, couplingmembers 546, 556 may be pivotably connected to a tie-rod arrangementwhich is translationally moved to adjust position of section 520relative to section 510. This alternative configuration may use ahydraulic cylinder or other type of linear motor to move the tie-rods.Besides a tie-rod or threaded shaft, other types of positioning membersmoveably engaging coupling members 546, 556 are envisioned.

System 500 enhances access to actuator 560 for maintenance purposes bymounting on the underside of expandable section 520. Nonetheless, inother embodiments motor 562 could be coupled to shaft 570 by gears orbelt driven pulleys and positioned elsewhere on section 510 or 520.Also, it is preferred that actuator 560 include governors or limiters toprevent damage to the actuator when an extension or retraction extremeof the adjustment range is reached.

Moreover, the arrangement of system 500 provides a reliable method ofmaintaining appropriate spacing between arms 544, 554. In otherembodiments a threaded shaft/threaded coupling member arrangement may befixed to arms 544, 554 near the interface with anchor brackets 542, 552,respectively. In one such embodiment an oblique portion may be usedsimilar to oblique portions 136, 146 shown for arms 130, 140 of theembodiment depicted in FIGS. 3-5. Generally, it is envisioned that thevarious features of the embodiments contained in FIGS. 1-16 may beadapted, combined, added, or substituted with the features of theembodiment contained in FIGS. 17-19 as would occur to one skilled in theart.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionare desired to be protected.

What is claimed is:
 1. A vehicle for providing adjustable occupant space, said vehicle comprising:(a) a first occupiable section with a number of ground engaging wheels and a first floor fixed to a first wall; (b) a second occupiable section coupled to said first section and having a second floor fixed to a second wall; (c) a carriage for supporting said second section and selectively positioning said second section relative to said first section to adjust volume of a living space defined by said first and second sections, said carriage including:(i) a first load bearing arm engaging said second section and pivotally anchored to said first section, said first arm being configured to rotate about a first axis to position said second section, and (ii) a second load bearing arm engaging said second section and pivotally anchored to said first section to rotate about a second axis to position said second section; and (d) an actuator with a stationary member fixed to said second section and a positioning member coupled to each of said first and second arms, said positioning member being configured to selectively move relative to said stationary member in response to activation of said actuator to rotate said first and second load bearing arms and correspondingly adjust said living space.
 2. The vehicle of claim 1, wherein said first and second axes are approximately parallel to each other and said second section moves in response to activation of said actuator along a third axis generally perpendicular to said first and second axes.
 3. The vehicle of claim 1, wherein said second floor is generally rigid and slidingly engages said first floor, said second section being configured to move along a generally horizontal plane.
 4. The vehicle of claim 1, wherein said first section defines a first interior space and said second section includes a pair of opposing walls fixed to said second floor and said second wall to define a second interior space intersecting said first interior space, said living space being adjustable by moving said second section to vary an amount of said second interior space contained within said first interior space.
 5. The vehicle of claim 1, wherein:said first arm includes a first coupling member pivotally mounted thereto, said second arm includes a second coupling member pivotally mounted thereto, and said first and second coupling members are engaged by said positioning member.
 6. The vehicle of claim 5, wherein said first coupling member defines a first threaded bore therethrough, said second coupling member defines a second threaded bore therethrough, and said positioning member includes a threaded shaft threaded through said first and second threaded bores.
 7. The vehicle of claim 6, wherein said actuator includes an electric motor configured to rotate said threaded shaft to move said first and second coupling members therealong and correspondingly rotate said first and second arms.
 8. The vehicle of claim 7, wherein said threaded shaft has an end portion journaled to said second section.
 9. The vehicle of claim 8, wherein said first section defines a first interior space and said second section includes a pair of opposing walls fixed to said second floor and said second wall to define a second interior space intersecting said first interior space, said living space being adjustable by moving said second section to vary an amount of said second interior space contained within said first interior space.
 10. A system for varying living space in a vehicle, said system comprising:(a) a first occupiable section with a number of ground engaging wheels and a first floor fixed to a first wall; (b) a second occupiable section coupled to said first section and having a second floor fixed to a second wall, said second section being movable relative to said first section to adjust volume of a living space defined by said first and second sections; (c) a first arm engaging said second section in a load bearing relationship and pivotally connected to said first section to rotate about an approximately vertical axis to position said second section relative to said first section, said first arm having a pivotally mounted first coupling member, said first coupling member defining a first threaded bore therethrough; and (d) an actuator with a threaded shaft engaging said first threaded bore, said actuator being configured to rotate said shaft to position said first coupling member therealong and correspondingly rotate said first arm to adjust said living space.
 11. The system of claim 10, further comprising a second arm engaging said second section in a load bearing relationship and pivotally connected to said first section to rotate about an approximately vertical axis to position said second section relative to said first section, said second arm having a pivotally mounted second coupling member, said second coupling member defining a second threaded bore therethrough, said shaft engaging said second threaded bore to position said second coupling member therealong and correspondingly rotate said second arm to adjust said living space.
 12. The system of claim 11, wherein said second section defines a slot, and said first and second coupling members include a slide block engaging said slot.
 13. The system of claim 11, wherein said actuator includes an electric motor with a stationary base fixed to said second section, said shaft includes a first end portion opposite a second end portion, said first end portion is coupled to said electric motor, and said second end portion is journaled to said second section.
 14. The system of claim 13, wherein said shaft is threaded through said first and second threaded bores between said first and second end portions.
 15. The system of claim 10, wherein said second floor is generally rigid and slidingly engages said first floor, said second section being configured to move along a generally horizontal plane.
 16. The system of claim 10, wherein said first section defines a first interior space and said second section includes a pair of opposing walls fixed to said second floor and said second wall to define a second interior space intersecting said first interior space, said living space being adjustable by moving said second section to vary an amount of said second interior space contained within said first interior space. 